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Posted:
Sat Dec 10, 2005 6:24 pmby blown928
Posted:
Sun Dec 11, 2005 12:17 pmby Mouse
Bill,
Refering to the relation of your test hole to the air source: If you place an orifice on the edge of your test hole nearest the air source, then move the orifice to the oposite edge of the test hole, the flow rate through your orifice may change because of the different angles the air can take through the test hole to the air source. If the air source is located directly below the test hole, this angle does not change.
John
Posted:
Sun Dec 11, 2005 1:33 pmby blown928
And would a tube under the test hole with a flow straightener fix that potential problem?
Posted:
Mon Dec 12, 2005 12:12 pmby Mouse
Hard to say. The only way to know is to try it. Air flow is very sensitive to changes and even harder to predict.
John
Posted:
Thu Dec 15, 2005 8:30 pmby Mouse
Just putting this thread back on top
John
Posted:
Mon Dec 19, 2005 5:17 pmby blown928
The KISS pressure sensor is up and runing. 2 differential channels, runs off a wall wart and outputs an analog voltage to my Dataq data logger....
Posted:
Mon Dec 19, 2005 6:10 pmby Thomas Vaught
Nice, let up know how it performs.
Tom V.
Posted:
Tue Dec 20, 2005 3:14 amby Nick
I've been looking for sensors, where did you get yours? I was just looking at the Dataq site. I would be interested in doing something very similar. I saw you can also export data directly to excel.
Nick
Posted:
Tue Dec 20, 2005 11:14 amby 86rocco
I recognize those sensors, they're the MPX2010DP by (aka Motorola), they're 0-10 mB differential pressure sensor, they're available from for $14.43 each. Personally, I'd prefer the MPX5010DP sensor instead, it's very similar except that it's output is amplified to fall inside the range of 0-5v, they're also available from digikey for $18.34.
There are also a couple of nice sensors in the Freescale MPXV7000 series, these sensor are similar to the MPX5000 series except they are bidirectional for example, the MPXV7007DP's range goes from -7.0 to + 7.0 mb, so there'd be no need to swap hoses or the like when switching from intake to exhaust. Honeywell also has some very nice bidrectional sensors but they tend to be a bit more pricey and harder to come by.
Posted:
Tue Dec 20, 2005 8:42 pmby blown928
Posted:
Tue Dec 20, 2005 9:29 pmby blown928
Posted:
Tue Dec 20, 2005 9:30 pmby blown928
Wow, must be more beat up that i thought, I'm seeing double!
Posted:
Wed Dec 21, 2005 12:22 amby Nick
My brothers are computer nuts, and insist that my old school manometers could be replaced with electronics to make life easier. So here is my question. If I used the sensors that had amplified voltage already, how do I wire it up. I was thinking that 2 pins go to 5v power and the other 2 go to the Data. Is it that easy? Are you willing to share your schematics? I'm not trying to put John out of business here, But I've built everything else on this property, so why stop now.
Nick
Posted:
Wed Dec 21, 2005 7:50 amby 86rocco
If your brothers are true computer geeks, you're more than halfway there, the toughest part is getting the software right, the hardware's easy.
First you'll need something to hook the sensors up to, a data aquistion device, personally I'll be using the but that's really overkill for this job, make a couple nice low cost units, either the DI-194RS or the DI-148U should do nicely. Then of course you'll need the the sensors, something like the , that sensor requires only 3 wires, a +5v supply voltage, signal voltage and a ground which is shared by both the supply and signal circuits. Hook the power and ground to the sensor with a decoupling capacitor close to the sensor, also hook the same ground up to the signal ground of the data logger and the signal voltage up to one of the analog inputs of the data logger.
Posted:
Wed Dec 21, 2005 10:17 amby blown928
The amplifier schematic I'm using is in this application note....